Modbus is a protocol in the industrial manufacturing and environment monitoring fields. It suits master-slave or query-response distributed I/O applications. The units have pre-installed a Modbus firmware. PC's, HMI's or PLC's can use Modbus/TCP and Modbus/RTU protocol to communicate with I/O modules in the unit via the RS-232/485 or Ethernet interface.

iP-8441-MTCP is a Modbus TCP I/O expansion unit to expand I-8K and I-87K series I/O modules over the Ethernet for industrial monitoring and controlling applications. There are more than 50 I/O modules supported with the unit, including analog input/output, digital input/output, counter, frequency I/O modules.Operating Temperature is from -25 ~ +75 °C
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iP-8811-MRTU is a Modbus serial I/O expansion unit to expand I-8K and I-87K series I/O modules over the serial port for industrial monitoring and controlling applications. There are more than 50 I/O modules supported with the unit, including analog input/output, digital input/output, counter, frequency I/O modules. It can operate under wide temperature (-25 ~ +75°C) More....